Because the LCD is incapable of actively emitting light at the present stage, the LCD needs to utilize a backlight module served as a light source. A conventional backlight source is a light emitting diode or a cold cathode fluorescent lamp, both of which are driven by electric power. However, the backlight source of the LCD accounts for about 80% of total power consumption of the whole system. Under long-term use, its energy consumption is very considerable. In types of power generation currently used, the main sources of the power generation are oil-burning power generation and nuclear power, and they bring problems of environment pollution, the greenhouse effect that causes climate change and other related environmental impacts.
Natural sunlight is green natural energy, and its spectrum contains visible wavelengths required for the backlight source. If the sunlight can be collected by using a light collection system to provide for the backlight source, the power consumption thereof can be greatly reduced.
However, no one has yet proposed such a sunlight collecting device that is capable of efficiently collecting the sunlight to serve as the backlight source.